“I understand that, sir.  It is no accident, her presence in the same house my mother occupied.”

“Well, as to that, you’re not sure.  That fellow who brought the news was paid to represent the head of the Valetta police, for they knew you had invoked official aid, and just as like as not he gave you an address that your mother never heard of.”

“Well, here we are!” suddenly.

“Eh?  This is the Strada Mezzodi?”

“Any objections to it?” laughing.

“Oh, no! one place is as good as another to me, in this Maltese city, where you seem to be climbing to paradise or descending into hades all the time.  Only I’m glad I came.”

“Why, professor?”

“Well,” with a look down the street, “I’m afraid you’ll need the services of a friend before long—­that you are about to experience a sensation you won’t soon forget,” replies Philander, coolly.

CHAPTER VI.

PAULINE POTTER’S HOUR COMES.

“It is possible!” declares John; “and under such circumstances I shall indeed be glad to have a friend in need.  At the same time it seems as strange to me to think Pauline Potter can be here—­that the Chicago actress whom I once adored and with a youth’s ardor swore to make my wife, can be here and bothering her head about one John Craig, M.D.”

“It will soon be known.  You have a good description of this house which the man supposed to be Luther Keene brought?” asks Philander, showing unexpected business qualities; indeed, he is proving more of a wonder to the young Chicagoan every hour.

“Yes, and can find it easily enough by the red lamp in front,” he replies.

“I see such a light along the strado.”

“That is, in all probability, our destination.”

They advance, and in another minute are at the door of the domicile marked so conspicuously with a red light.

John allows himself a brief period of ecstasy as he remembers that his mother crossed this threshold only recently, and in his eyes this renders it holy.

Then he recovers his common sense, and is once more the wide-awake, vigilant John Craig who met the advance of the mad dog so coolly upon the hill road of Valetta.

“There’s a knocker,” says the professor.

“I’ll try it,” John replies, and as he swings the weight a ponderous sound ensues, a hollow clamor that is loud enough to arouse the whole street, John thinks.

“Great guns!” mutters Philander, “it’s a great piece of luck there’s no grave-yard near.”

“How’s that?” demands his companion.

“Well, that clang would arouse the dead,” is the amazing reply.

Further conversation is cut short by the sound of footsteps within—­a bolt is withdrawn, proving that the inmates of the house on the Strada Mezzodi do not have the Maltese sense of honor that makes the presence of locks and bars unnecessary.